The invention relates to molten metal samplers, particularly adapted for forming a pin sample which can be used in a combustion analyzer or other analysis equipment for determining various properties of the sample, and hence, properties of the molten melt from which the sample is obtained. The molten metal sampler can be pre-evacuated and thus can provide a sample without an oxide coating which avoids the necessity of removing the oxide surface by machining prior to certain types of analysis. The sampler can be sized to interfit in gas analysis equipment such as that manufactured by Leco Corporation and referred to in U.S. Pat. No. 4,445,390.
When used for analysis of hydrogen, the prior art samplers, such as that disclosed in U.S. Pat. No. 4,445,390 and U.S. Pat. No. 3,967,505 employ closure or screen means to separate the inner sample chamber from the outer evacuated chamber or housing and permit gases evolved from the sample chamber during sample rooting to enter the outer chamber but prevent molten metal from entering the outer chamber. The gases evolved during cooling become accessible in the outer chamber or housing for retrieval and analysis. The closure means enables release of all gases including oxygen, nitrogen and hydrogen evolving from the cooling sample. One of the objects of samplers of this category is to provide a good seal at the inlet end of the sample mold as the metal cools to prevent outflow of metal and also seal the evolved gases in the sampler for later analysis. The prior art techniques have not consistently provided good results.